With a sharp knife, punch a hole about two inches deep in the roast.,Insert a clove of garlic.,Repeat till all the garlic is used.,______,Place in a large glass container, mix the marinade ingredients, and pour over the roast.,Chill 12 to 24 hrs, basting often with the marinade.,Place the roast in a large Dutch oven or possibly roasting pan.,Pour the marinade over the meat, and cook in a 225-degree oven for about four hrs.,Add in mushrooms to the pan for the last hour of cooking.